Meeting Abstract
Males of many species produce signals that aggregate conspecifics and attract mates. Males can alter signals in response to competitors. Relative to other sensory modalities, little is known about how chemical signals affect competition. The chemical communication system in sea lamprey, Petromyzon marinus, is well understood and offers a model to study the influences of chemical signals on male-male competition. Male sea lamprey aggregate on spawning grounds where they build a nest and signal to females using sex pheromones. A major component, 3keto-petromyzonol sulfate (3kPZS), induces short and long distance upstream movement of sexually mature females. Here, we examined the male response to simulated competition using 3kPZS as a stimulus. Simulated competition led to an immediate increase in 3kPZS release rate within ten minutes followed by a reduction to baseline levels over the course of an hour. Exposure to 3kPZS also led to increased bile acid synthesis and transport in tissue and plasma samples. This increase could be due to up-regulation of specific enzymes responsible for bile acid production and transport. Based upon our results, we suggest that by increasing synthesis and release, males improve their chances of matching or possibly exceeding competitors’ signals, allowing them to better compete for mates.
